Purpose: :
GABAC receptors (GABACRs) in the mouse retina are highly expressedon axon terminals of bipolar cells, particularly rod and ONcone bipolar cells, but are also present more distally on thosecells. GABAARs, while present on bipolar cells, are also foundon amacrine and ganglion cells, and in distal retina. This studyinvestigated functions of these different ionotropic GABARsin retina by studying effects on mouse electroretinogram (ERG)of using receptor antagonists and agonists, or genetic deletionof GABACRs.

Conclusions: :
These results suggest an excitatory role for GABA via GABACRsin mouse retina. GABACRs on ON bipolar cells that generate ERGb-waves must be functional for normal maximum amplitudes tobe achieved. Results for GABAARs on inner retinal ERG signals(and effects of GABAcRs on OPs) are consistent with the knowninhibitory role of GABA on amacrine and ganglion cell signals.